I think I need an upgrade

The E-PM2 and E-PL5 have live bulb as well.

 

e-pl5, but i am biased i have one  

 

I also went from EPM1 to EPL5 (after considering the OMD) and very very happy with the upgrade.

I loved the small size of the EPM1 and felt the OMD - although extremely capable with useful extra controls - was just too large.
Especially as I've downsized from Canon SLR gear, this would've been too much of a regression in size for me.

The EPL5 is slightly more bulky than the EPM1 due to the folding screen. I also feel more "precious" about it, as if it's more delicate.

The image quality is a huge leap forward. For example I had Auto ISO set to 1600 on the EPM1, but at 6400 on the EPL5 and sometimes use higher than that.

I use the flip out screen far more than I expected.
It was worth paying the extra money for that and the mode dial over the EPM2 for me. The mode dial has helped me enjoy using the camera seriously.

 

The E-PM2 and E-PL5 would both fit all your criteria and are available for much cheaper than the OM-D E-M5. I think the choice is pretty simple. All that's left to decide is if you want to pay more for a tilt screen, or if you want to pay less and get a slightly slimmer package.